VAN2000080203 - 02 AUGUST 2000 - VANCOUVER, B.C. CANADA: A partial solar eclipse of the sun as seen over Vancouver reaches its maximun effect at 8:08 pm Sunday, July 31, with the moon blocking 32.7 percent of the sun. cc/hr/H. Ruckemann UPI

A solar eclipse occurs when the moon passes between the Sun and the Earth so that the Sun is fully or partially covered. This can only happen during a new moon, when the Sun and Moon are in conjunction as seen from the Earth. At least two and up to five solar eclipses can occur each year on Earth, with between zero and two of them being total eclipses. Total solar eclipses are nevertheless rare at any location because during each eclipse totality exists only along a narrow corridor in the relatively tiny area of the Moon's umbra.

A total solar eclipse is a spectacular natural phenomenon and many people travel to remote locations to observe one. The 1999 total eclipse in Europe helped to increase public awareness of the phenomenon, as illustrated by the number of journeys made specifically to witness the 2005 annular eclipse and the 2006 total eclipse. The recent solar eclipse of January 26, 2009, was an annular eclipse (see below), while the solar eclipse of July 22, 2009 was a total solar eclipse.

In ancient times, and in some cultures today, solar eclipses have been attributed to supernatural causes. Total solar eclipses can be frightening for people who are unaware of their astronomical explanation, as the Sun seems to disappear in the middle of the day and the sky darkens in a matter of minutes.

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